It has long been a goal in the water heater industry to continue to improve so-called “first hour ratings.” The first hour rating is an approximation of the usable hot water that a water heater can supply within an hour that begins with the water heater being fully heated. Beyond first hour ratings, it has also been desired to obtain a substantially continuous supply of hot water. Increasing the first hour rating, establishing substantially continuous hot water and at the same time decreasing overall energy usage is desirable.